Glowproofing composition comprising phenol-aldehyde resins and water-insoluble reaction product of phosphoryl chloride and anhydrous ammonia



Patented May 13, 1952 iGIJOWPRGO INGooMrosicrroN "COMPRIS- "ING "PHENOL -ALDEHYDE RESINS AND \WATERZINSOLUBLE REACTION PRODUCT "TOF- rnosenoavnc CHLORIDE-AND? ANHY- mtoUs AMMONIA :i or'ris L. Nielsenfand HowardlKJ Nason, Dayton,

Ohiofatss'ignbrs to Monsanto Chemical Com- *panyfSt'i Louis? Mo.. a corporation ofDelaware i No Drawing. iepplication December 30, 1948, I Serial No. 68,405

l Thisinvention relates to new" compositionsiof matter" and'to' the manner of"producing them. The "invention specifically relates to "materials having utility in fiameproofing compositionsiwith T the particular 'obiective of reducinglthe "tendency to" exhibit 'after glow. It" is 'an' object. of "the invention "to? provide a composition of ma'tter'which maybe combined with, "'or applied 'to" combustible products to re- "duce' the danger of after glow,"which.is' known to ""bea'property common to resinous materials. Thefinventlon likewise Prelates to a preferred method for producing these compositions.

In accordance with the terminology which has developedinthis'field' flameproofing meansthe treatment of' a materialso that it is resistant :to ""the'ipropa'gation offiame across its; surface after theig'niting flame has'been removdyth'atis; a properly flameproof'ed' materialwill "not support combustion independently of an external source ofheat. In contact with an open flame, however, or atlelev'atedtemperatures;flameproofed or anic "materials*canbe'expected to char and decompose. "'The technical term" fflameproofing :is used herein according to 'the'definitions and require "mentsset""forthfin the ASTMStandatds 1944 Yearbookiunder' Test (D626F-41T) BS 111,. 1930 and also 'the Army Quartermaster Corps "Test JQD 242.

" In. the problemof reducing theidanger-of' fire in the use. of various resins; particularly in the caseor resins which do not" contain :nitrogen; it is obvious that the large proportion of carbon, hydrogen and oxygen which are present in such resins, renders thesematerials particu arly sue-H .ceptible to combustion. T'Even such resinous ma .teri'als as the 'phenolic resin class ofmater als :':have been found .to g'low excessively after ithev have been in contact with a fla e, so lthat such .a"slow combu'stion or after-glow -ma,v entirely --con.'su'me"t he resinous material, e en where only 2a portion thereof hadactually been.v consumed by flaming combustion. Such effects are particularly'dang'erouslin coating compositions. or other "extendedfor dispersed surfaces of lar e area,

whmnmay by this means propagate a fire even "thmigh'it may appear 'toh'ave been extinguished at one point, since" the" after 'g'low phenomenon may permit the fire to be propagated to other portions of the coating film',"where other combustiflameproofing treatments, combination with polyvinyl chloride or chlorinated parafiln; aidin the catalytic efie'ct'which appears'tobeithecause of the after glow phenomenon. For thisreason the initial pyrogenic'dec'ompo'sition oftheoellulose. 'Thus, the' metal oxides" fthatf areinstrumental in bringing aboutthe desirable suppres- "sion' of 'the'initial' fire or'pyrogenic decomposition may be primarily responsible" for" theproductlon of an undesirable after-glow or flameless-combustion.

The present invention provides. compositions which reduce the after glow 'in con ibustible'materials such as resins,'particularlythe group of phenol-formaldehyde and ifres'orcinol formaldehyde resins.

The process of the invention "may be carried out to obtainfiamepro'ofed products'whi'ch avoid the prior art difiiculty -of after-glow.

It has been found that I fiam'eproofingresinous compositions employed in combination with an otherwise combustible base material may beimade with a. negligible vafter-glowperi'odif combinations' include the reaction produ'otpi phosphoryl chloride and ammonia, as described'by'Mellor in Comprehensive Treatise. onln'organic and: Theoretical Chemistry; 8; 713 "(Longmana Green and j Company; 'New York, 1928). In 'particularthe reaction product of phosphoryl ohlorideand ammonia which has been designated as'polyphosphorylamide; and which is aninsolubleinfusible, white powder-{is of utility'in this"'relationship. The preparationlof this material isdescribed'in co-pen'ding application'Serial No. 68,402; filed December 30,1948 and assigned tothe same ass'i'gnee as is'the present case. Polyphosphor-yl'amide' may 'Tbe produced as aninsolublegmaterial whichin contact with -Walll exhibits a neutral oriislightly alkaline reaction; without; however; undergoing any appreciable hydrolysis. at room temperature. The. process ismost, conveniently carried .outby .ride) dissolved .in a hydrocarbon solvent .boiling above 2.00 .0. mm at least im'oles. oft ammonia added and combined therewith. Itihas been found that a definite compound is formed. atflthis stage, althoughmore ammonia mayLbeadded.

The reaction is best carried. out. at temperatures below 100" c. and preferably above 20 o., utilizing normal pressure or elevated pressure. Since exothermic reaction heat is liberated it is desirable to cool the hydrocarbon solution during the reaction in order to maintain the temperature thereof between the above limits. The product formed by this initial reaction is a fine, white powder which consists of a mixture of a nitrogenphosphorus containing body and ammonium chloride. The nitrogen-phosphorus containing body is at this stage water-soluble and alkaline in reaction. If desired, the reaction product may now be separated by filtration or by centrifuging from the hydrocarbon and the separated product treated according to the second step of our process.

Preferably the heating step may be carried out upon the reaction product produced by the first step while the product is still suspended or mixed with the original hydrocarbon solvent. This results in better yields and simpl fied operation, since the material may be handled more easily and without losses. The second step of our process involves heating the product produced in the first step to a temperatue abo e 155 C., but below a temperature of 250 C., either at atmospheric or superatmospheric pressure. During the heating period. a small amount of ammonia is evolved which may be recovered and reused in the process. Durin the heatin step the nitrogen-phosphorus product apparently undergoes a polymerizatinn or m lecular rearran emnt. being converted thereby into a water-insoluble product of higher molecular weight.

Example A One hundred parts of phosphoryl chloride was dissolved in 300 parts of kerosene 01' commercial grade. The kerosene had a boiling range of about 150 to 260 C. Anhydrous am onia gas was then passed into the kerosene solution at a slow rate of addition, and simultaneously therewith, the solution was cooled in order to maintain the temperature below about 80 C. At the same time, efiic ent agitation of the solution was maintained. The addition of ammonia was continued in this manner until 5 moles of ammonia had been reacted with the phosphoryl chloride. The reaction product was insoluble in kerosene and appeared as a white powder suspended therein.

After completion of the ammonia addition, the reaction mixture, while remaining suspended in kerosene, was heated to a temperature of 200 C. After the temperature had reached 200 0., heating was discontinued and the mixture permitted to cool. During the heating period, some ammonia was evolved, the nitrogen-phosphorus product apparently undergoing polymerization and becoming water-insoluble. At the end of the heating period, which may be carried out for a period of from one-fourth to three hours, preferably one to three hours, the solids were removed from the kerosene by filtration or centrifuging. The product was next washed with water in sufiicient amount so as to dissolve the ammonium chloride present in the product. The washing operation may also be followed by a heating step which is designed to dry the product and also to remove traces of the kerosene or, other hydrocarbon. A convenient method for removing the hydrocarbon consists in steaming the product while it is contained in a rotating centrifuge.

The nitrogen-phosphorus containing product, resulting from the present process, is substantially insoluble in water as well as organic solvents. It may be suspended or dispersed in water and will then exhibit a pH which is substantially neutral or alkaline in reaction. The final prodnot is free from chlorine as a result of the heating and polymerization step, which makes it possible for the ammonium chloride to be completely removed to leave only the condensation product consisting essentially of nitrogen, oxygen, hydrogen and phosphorus. The nitrogen-phosphorus atomic ratio is approximately 1.80:1, but may be varied within the range of 1.5:1 to 20:1 by variation of the amount of NH; initially reacted with the POC13 and this product to some degree polymerized, and then subjected to heating as described above, to complete the polymerization. The preferred NzP ratio suitable for most purposes varies from 1.70:1 to 1.95:1.

The phosphorus-containing reaction product of phosphoryl chloride and ammonia functions in the combination with the phenolic type resin to reduce the above-described phenomenon of afterglow.

The combination products based upon the phenolic resin in association with the reaction product of phosphoryl chloride and ammonia are products which may be utilized in producing sheets of resinous or plastic materials or in the manufacture of formed, plastic articles of various types such as may be produced by molding, extrusion, casting, stamping and other processes.

The composition of matter employed in the present application may be prepared by the dispersion or mixing of the polyphosphorylamide in the phenolic condensation product while in the liquid or paste form. However, it may also be mixed with the resin while the latter-is in the Example 1 A suspension prepared from a heat-reactive condensation product of resorcinol and formaldehyde in the form of a paste. Such materials are described in C. Ellis, Chemistry of Synthetic Resins, pages 371-373 (Reinhold Publishing Company (1933)). One hundred parts of the condensation product were mixed with 5 parts of the polyphosphorylamide. The combination was applied as a coating to metal panels and dried. These test panels, when subjected to a flame test similar to that shown by R. W. Little in Flameproofing Textile Fabrics, pages 111-115 (Reinhold Publishing Company (194'7) gave no afterflame or after-glow.

Example 2 A phenol-formaldehyde molding powder of a type shown in Ellis, at pages 277-290 was mixed with 30%, by weight, of polyphosphorylamide. The mixture may be molded or formed into any desired shape to give resinous products which do acetates .235 not burn and whiclr doznot permit any after-glow or smoldering.

Er mrler #brgaiii sor- The combination mixtureeof Example 2 was l. l

1. .v has. r reaction productofphosphorylchloride"and andispersed on glass fibers of small diameter and hydrous ammonia; V

T SriaI'PNQS 68,410? filed Decemb'e 30, -1"9 i8;'relitting to' thecombinatiombf he atei ins'oluble e'a non-premierbr bhebpho ydrous amnio'riia togther with chlorinatd rubwhen subjected-to ailamej did "bt bur-n and 'did ze'rrot xhibit any after-glow. A ontrol' 'sainple of.

phenol-formaldehyde on: iglasse-fibers, identical 9 her but for the absence of the polyphosphorylamide, a L v a showed a-prolonged glowingperiod after'removal n g l .m' "irom-a -t'est-fiame. -'G1ase-hbere treatecidn the flameprmfefiwemlt r member manner ofithef present.fexampie, isuch as by the .FP K P F ,WWW??? Ether tii f w a use, of from 3.%- to 50%, .byweight, vofthe phenolic lage e pg? iresin heiybhcsphbrymmiaegnavefalse beeriround 9 f. i my)? 6 be be useful as "filt'rsfihicfidd nbt bum-end i 55; e will not glow after contact with a flame. Other -h or. f i 1.3, siliceous materials, particularly in attenuated, in UP?? 9 3.99)? a 9 @Wi, g form, such as fibrous silica, mineral wool, and f m i i P m Teacmon'pmfiuigtm'phos' cellular glass, may also be bonded to give a glow- WW I E fiqQE -Q np ainmoma together proof product by means of the present combinawithiantlmonyvxlde!and chlormated paraflins;

Serial No. 136,136, filed December 30, 1949, re-

tion of a phenolic condensation product together lating to compositions comprising the combinawlth condensatmn product of phosphorylchlo 2 tion of the reaction product of phosphoryl chloride as et forth above. 5

The p roportion of the phosphorus compound in ride and anpydrous ammoma together wlth comassociation with the phenolic resin may be varied ggggggfiz free hydmxy radmals Such as over Wlde range dependmg upon the degree of Having now described certain specific forms of fire-retardmg and glowpmofing efiects deslred' the invention, it is to be understood that the in- It has been found however that the essential vention is not to be limited to the specific forms composition consisting of the phenolic resin, such of compositions herein described or specifically as phenol-formaldehyde, resorcinol-formalded b th I hyde and mixtures of the same, and the Poohag t 1 f d i d t b t t d ammonia reaction product should contain at least b a 1 g f z 9 80 e 3 parts, and preferably not more than 90 parts, y ers en 9 e n a es by weight, of said PoClg-ammonia condensation 1 5: 3;?zg sgiggg q ggfiggggggigg 2:

me per 100 parts by weight of the final mix- Water-insoluble reaction product of phosphoryl chloride and anhydrous ammonia, said water-in- This application contains subject matter in common with certain other applications assigned 40 $33 P havmg N/P mm) between to the same assignee as is the present application:

Serial No. 68,402, filed December so, 1948, re- 4 9 mmprismg the lating to the water-insoluble composition of matcombmatmr; a phergl'aldehyde resin of the ter resulting from the reaction of phosphoryl group conss ng of p embfmllaldehyde' and chloride and anhydrous ammonia; resorcinol-formaldehyde and mnrtures of the Serial No. 68,403 filed December 30, 1948 same, which resin is associated with the waterlating to a water paint comprising a dispersion insoluble reaction product of phosphoryl chloride of the water-insoluble reaction product of phosg i Said c f g phoryl chloride and anhydrous ammonia in compro uc avmg N/ m between an bination with water-soluble, nitrogen-containing resinous materials; 3. glowproofing composition comprising the serial 68,404, filed December 1943, combination of a resoromol-formaldehyde resin and the water-insoluble reaction product of phosphoryl chloride and anhydrous ammonia, said t f h h l h e nd water-insoluble product having a N/P ratio be- ?g g g gggg g q osp oryl owe 1O 1 e a an tween 1.5:1 and 2.0:1, which latter reaction prod- Serial No. 68,401, filed December 30, 1948, reis P 3 3 3% 90% by lating to intumescing compositions comprising Welght m sald composltlon' t the combination of a nitrogen-containing resin in 9 composl Ion P he combination with the water-insoluble reaction combmatlon of phenol'formaldehyde resm and product of phosphoryl chloride and anhydrous the water-insoluble reaction product of phosphoryl chloride and anhydrous ammonia, said lating to a flameproofing treatment for cotton by the application thereto of the water-insoluble rei f i 63,407, filed December 30, 1948, water-insoluble product having a N/P ratio belating to water paints based upon the combina tween 15:1 and 2.021, which latter reaction prodtion of the water-insoluble reaction product of f is preseflt to the of 3% to 90% by phosphoryl chloride and anhydrous ammonia to- Welght of Sald P gether with water-soluble alkyd resins derived The method of p duc n'g a glowproof, nonfrom the reaction of citric acid and glycerine; combustible material Which comprises eat serial No, 3,403, filed December 30 943 said material with a dispersion containing the lating to water emulsion paints comprising the insoluble, heat-reaction Product Of p p ry combination of a nitrogen-containing resin and chloride and anhydrous ammonia, S Wate -inthe water-insoluble reaction product of phos- Soluble product having N/ r tio between 1.5:1 phoryl chloride and anhydrous ammonia together and Which p c is a iated with a with polyhydroxy compounds such as pentaephenol-aldehyde resin.

rythritol; 6. An insulating material comprising glass fibers rendered glow-proof by the dispersion thereon of a phenol-aldehyde resin associated with the insoluble, heat-reaction product of phosphoryl chloride andanhydrous ammonia, said water-insoluble product having a N/P ratio between 1.5:1 and 2.0:1.

7. A composition of matter comprising an otherwise glow-susceptible phenol-aldehyde resin, which resin has been rendered glowprooi by the addition thereto of from 3% to 90% by weight 10 of the water-insoluble reaction product of phosphoryl chloride and anhydrous ammonia, said water-insoluble product having a N/P ratio between 1.5:1 and 2.0:1.

8. An air filter comprising an attenuated, siliceous material in combination with a phenolaldehyde resin and the water-insoluble condensation product of phosphoryl chloride and anhydrous ammonia, said water-insoluble product having a N/P ratio between 15:1 and 2.0:1

MORRIS L. NIELSEN. HOWARD K. NASON.

8 REFERENCES crrEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date I 2,052,886 Leroy Sept. 1, 1936 2,163,085 Cupery June 20, 1939 2,413,163 Bacon Dec. 24, 1946 I FOREIGN PATENTS Number Country Date 181,547 Switzerland Mar. 16, 1936 OTHER REFERENCES Mellor, Comprehensive Treatise on Inorganic and Theoretical Chemistry. vol. 8 (1928); pages 704-720. 

1. A GLOWPROOFING COMPOSITION COMPRISING THE COMBINATION OF A HENOL-ALDEHYDE RESIN AND THE WATER-INSOLUBLE REACTION PRODUCT OF PHOSPHORYL CHLORIDE AND ANHYDROUS AMMONIA, AND WATER-INSOLUBLE PRODUCT HAVING N/P RATIO BETWEEN 1.5:1 AND 2.0:1. 